An issue was discovered in Valve Steam Link build 643. When the SSH daemon is enabled for local development, the device is publicly available via IPv6 TCP port 22 over the internet (with stateless address autoconfiguration) by default, which makes it easier for remote attackers to obtain access by guessing 24 bits of the MAC address and attempting a root login. This can be exploited in conjunction with CVE-2017-17878.
Conclusion & alert: CVE-2017-17877 is rated High Risk (73.3/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 4.10%). Core evidence: EPSS rose +2.76% over the last day, indicating growing attacker interest. Mandatory action: High exploitation likelihood—assess exposure and prioritize remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-15 | 1.34% | 4.10% | +2.76% |
| 2 | 2025-03-30 | 4.11% | 1.34% | -2.77% |
| 3 | 2025-03-29 | — | 4.11% | — |
Full EPSS history (14 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 9.8 | 3.0 | CRITICAL |
|
3.9 | 5.9 | [email protected] |
| 10.0 | 2.0 | HIGH |
|
10.0 | 10.0 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| valvesoftware | steam_link_firmware | < 644 | cpe:2.3:o:valvesoftware:steam_link_firmware:*:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://blogger.davidmanouchehri.com/2017/12/steam-link-security-remotely-insecure.html | Issue Tracking Third Party Advisory |
| https://github.com/ValveSoftware/steamlink-sdk#ssh-access | Issue Tracking Third Party Advisory |
| https://github.com/ValveSoftware/steamlink-sdk/issues/119 | Issue Tracking Third Party Advisory |